Physical quality of an Oxisol with nine years with integration system livestock

Abstract

Crop-livestock integration systems are an alternative to maximize the income of the rural farmer and to compose systems of rotation of crops under no-tillage system. However, concern about soil compaction generates questions about the sustainability of the system. Is this sense, a long-term experiment was set up in 2006 to evaluate nitrogen rates in crop system with integrating livestock farming with sheep. The aim of this study was to evaluate the effect of different nitrogen rates and grazing with sheep on behavior of the soil physical attributes of long-term agriculture-livestock integration system. The experimental design was in randomized blocks with subdivided plots with three replicates installed on Oxisol with very clayey texture. Nitrogen rates represent the plots and the subplots were composed by presence or absence of grazing. Nitrogen rates were 0, 75, 150 and 225 kg ha-1 applied to the ryegrass pasture in winter period. The number of animals per experimental unit was variable as a function of grazing height (0.20 m), which was achieved by introducing or removing regulatory animals. There was no statistical effect of the nitrogen factor on the soil physical attributes. Bulk density, macroporosity and resistance to soil penetration were negatively affected by grazing at the soil surface layers.